original, and extract the numbers within the configure script.
* configure.in: extract the numbers from lib/expat.h
* Makefile.in: simplify the construction of DISTDIR
* lib/Makefile.in: no need to define the VERSION preprocessor symbol
* lib/expat.dsp: do not define VERSION (changed, but untested!)
* lib/xmlparse.c: revamp the XML_ExpatVersion() function
* lib/expat.h(.in): just ship the baby, rather than generating it